Stock-Based Compensation and Employee Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2023

Compensation Related Costs [Abstract]

Schedule of Employee and Non-Employee Stock-Based Compensation Expense

The following table summarizes the components of stock-based compensation expense in the consolidated statements of operations (in thousands):

	Years Ended December 31,
	2023		2022		2021
Cost of revenue	$	17,504	$	18,955	$	13,811
Research and development	27,620		33,956		20,274
Sales and marketing	16,415		18,651		17,085
General and administrative	25,556		42,404		24,962
	$	87,095	$	113,966	$	76,132

Schedule of Stock Option and RSU Activity

The following table summarizes the stock option activity under our stock plans during the reporting period:

	Outstanding Options
	Number of Shares	Weighted Average Exercise Price		Remaining Contractual Life (Years)	Aggregate Intrinsic Value
					(in thousands)
Balances at December 31, 2021	10,737,295	$	21.23	5.2	$	60,304
Exercised	(537,324)	7.08
Forfeited	(42,774)	6.98
Expired	(1,408,888)	30.39
Balances at December 31, 2022	8,748,309	$	20.70	4.6	$	40,532
Exercised	(525,031)	6.76
Expired	(975,654)	26.58
Balances at December 31, 2023	7,247,624	$	20.93	3.8	$	19,446
Vested and expected to vest at December 31, 2023	7,241,265	20.93		3.8	19,444
Exercisable at December 31, 2023	7,230,957	20.96		3.8	19,321

The following table presents the stock activity and the total number of shares available for grant under our stock plans:

	Plan Shares Available for Grant
Balances at December 31, 2021	24,146,784
Added to plan	8,384,460
Granted	(5,431,930)
Cancelled/Forfeited	2,597,990
Expired	(1,356,663)
Balances at December 31, 2022	28,340,641
Added to plan	8,948,255
Granted	(6,290,060)
Cancelled/Forfeited	2,774,990
Expired	(895,920)
Balances at December 31, 2023	32,877,906

Schedule of RSU Activity and Related Information

A summary of our stock awards activity and related information is as follows:

	Number of Awards Outstanding	Weighted Average Grant Date Fair Value
Unvested Balance at December 31, 2021	8,367,664	$	20.52
Granted	5,395,199	19.74
Vested	(2,957,215)	18.14
Forfeited	(1,256,613)	21.32
Unvested Balance at December 31, 2022	9,549,035	$	19.99
Granted	6,369,823	17.33
Vested	(4,160,416)	19.55
Forfeited	(1,869,101)	21.12
Unvested Balance at December 31, 2023	9,889,341	$	18.25

Schedule of Weighted-Average Valuation Assumptions

We used the following weighted-average assumptions in applying the Black-Scholes valuation model for determination of the 2018 ESPP share valuation:

	Years Ended December 31,
	2023	2022
Risk-free interest rate	4.9%-5.6%	3.1%-3.2%
Expected term (years)	0.5-2	0.5-2
Expected dividend yield	—	—
Expected volatility	54.1%-74.1%	78.0%-88.9%